What happens if the following program is executed in C and C++?

#include<stdio.h> 
int main() 
{ 
   foo();
}  
int foo() 
{ 
   printf("Hello"); 
   return 0;  
}

A. .cpp B. .cc C. .cxx D. .c

A. char B. float C. boolean D. double

A. File output stream B. File input stream C. Standard output stream D. Standard input stream

A. struct B. interface C. class D. object